The present invention relates to transmission of probe-specific set up data in a probe adapted for use with an automatic tank gauge system, and in particular transmission of such data in connection with uni-directional probes which are output-only, generating continuous data regarding measured parameters.
Typically, uni-directional probes for measuring liquid levels, such as those which employ a well-known magnetostrictive linear position detector, send data to a processing unit via measurement data protocol which is defined by frames of data, subdivided into a plurality of slots. Each of these slots contain a reference pulse typically sent at a start of the slot, and a return pulse which lags the reference pulse by a particular timing which is representative of a parameter being measured. The inter-pulse timing, i.e., the period between the reference pulse and the return pulse is converted into the value of the measured parameter, such as for example, position of a magnet or temperature value, by the processing unit receiving the transmitted data from the probe.
Probes of this type generally include probe-specific data regarding structural configuration and characteristics unique to the particular probe. These include, for example, probe sensor length, wire speed, etc.
Conventionally, such data is included as printed matter carried on the probe, which data is input by a user into a processing system which receives and analyzes measurement data from the probe transmitted thereto in accordance with conventionally known probe measurement data protocol. When a probe is replaced, data entry is necessary for at least a portion of the characteristics which differ from the replaced probe and the one substituted therefor in order to assure accurate measurements based upon true characteristics peculiar to each unit. Failure to calibrate the tank gauge system upon probe replacement has heretofore presented a significant drawback, by resulting in subsequent gauging inaccuracies.
It is therefore an object of the invention to provide a method of transmitting probe configuration data which overcomes the drawbacks of the prior art, and by which such probe-specific data is transmitted to the tank gauge system processor, thereby obviating the heretofore requirement of manual entry.